Apparatus for the determination of brinell-numbers



May 28, 1935. -s. L. E. FALK APPARATUS FOR THE DETERMINATION OF BRINELL-NUMBE Filed Aug. 1,' 19:52

Passed Meyzs, 1935" UNITED "STATES PATENT OFFICE amass mmrnsroa 'rnr: DETERMINATION or nanvmrxummas Stig Lennart E:Son fastens, Sweden A plication August 1, 19:2. Serial No. 021.211

In Sweden August a, 19:1 sci-ins. (01. 265-12) I in question under a certain load, which is selected so that the ball makes a remaining impression in the material. The penetration of the ball into the material is a measure of the hardness thereof,

and the number oi the hardness is indicated by the load applied to the ball, expressed in kilograms, divided by the curved the so- V called calotte formed in the material, expressed in square millimeters.

' v The invention relates to an apparatus for l! determining the hardness of a material by the Brinell method, which is simple and inexpensive in manufacture and which can beused ior making a quick test in a work shop. It further has the advantage that it can be used over a widetest range; that the means or exerting the pressure can be easily calibrated; and that it is unstressed in the non-operative state 0! the apparatus.

In the accompanying drawing Fig. 1 represents a side view of an apparatus according to the invention and Fig. 2 shows a section through the handle on the line 2-2' of Pig. 1.

In the drawing, I and,2 designate the two shanks oi. the tongs which are pivotally connected with each other by means of a hardened 80 pivot 3 running in steel bushings [pressed into the shanks. Attached to the shorter arm of the shank I is the anvil I, and to the shorter arm of the shank 2 is secured a set-screw Q carrying the exchangeable ball holder I adapted for dif- 85 ferent balls, (This arrangement is well known and need not be further described here; it is not part or the present invention; Attached to the longer arm or the shank I by means of the screws 8 is an exchangeable and calibrated spr ng 9. At- 40 the free end the spring is provided with a handle I0 secured to the spring by means of the screws I1. Arranged on the handle II is an auxiliary handle or the like I2 pi oted to the handle Il by means 01' screws II. The longer arm of the 4s shank 2 is provided at its free end with a strap I2 pivoted about the point II and constructed so as to form an abutment for the shank I'when in the swung-up position shown in thedrawing, so that the shanks I and 2 may be adjusted into 50 a definite initial position relatively to each other. Furthermore, means are provided to limit the movement of theshanks toward each other in the use of the apparatus, said means comprising a set-screw I! on the handle and an'abut- 55 meat It on the shank 2'.

into different In the use, of the apparatus the object to. be tested is inserted between the anvil 5 and. the ball holder I, the strap 12 is swungup, and the shank I is causedto bear on the strap IS in the initial position. The screw 6 is then adjusted so 5 that the ball touches the test piece, whereupon the strap I3 is swung down and the two shanks are approached to each other manually or by means or a clamp, until the set-screw I6 is brought into contact with the abutment Ii. 10 Here, the force is applied between the auxiliary handle I2 and the free end of the shank 2, and

' on account of the suspension of the auxiliary handle at the point II and the limitation of the movement through the set-screw I! and the 5 abutment I, the force acting between the anvil and the ball holder will always be the same for a given spring. The impression is then measured as usual, and with the knowledge of the force acting between the ball holder and the an anvil, the Brinell-number may be calculated. For an accurate determination due regard is to be paid to the variation in the magnitude of the power caused by the steel ball being pressed materials in a varying degree. To 5 this end a table may be made up on the basis of comparative tests. For less accurate measurements, however, the apparatus may be used without taking this precaution and then offers the advantage of being readily transportable and 3Q simple to use, so that the hardness of bulky ma terial may be determined directly in the workshop.

- What I.cl'aim is:

1. Apparatus for the determination of the degree oi hardness of materials in accordance with the so-called Brinell method comprising a pair of tong members pivoted to provide a pair or jaws, a ball holder and an anvil positioned on the opposing jaws, respectively, and means to 40 subject the ball to be tested to a controllable spring pressure, said means comprising an exchangeable and calibrated flat spring member extended in prolongation of the shank of one of said-tong members and so arranged as to be unstressed in its initial position.

2. Apparatus for the determination of the degree of hardness of materials in accordance with the so-called Brinell method comprising a pair or tong members pivoted to provide a pair 01. jaws; a ball holder and an anvil positioned on the opposing jaws, respectively, means to subject the ball to be tested to a controllable spring pressure, said means comprising an exchangeable and calibrated flat spring member extended in 56 prolongation or the shank of one or said ion: the ball 'to be tested to a controllable spring members, and means to prevent the spring from pressure, said means comprising an exchangeable .being stressed in the initial position of said and calibrated fiat spring member extended in p ingprolongation of the shank of one of said tong 5 v 3. Apparatus for the determination of the demembers, and means including a latch member '6 sree of hardness of materials in accordance with pivotally attached to the extended shank of the the oed. Brlnell me d comprising a p ir other of said tons members to prevent the pring '1 s em ers pivoted to provide a pair orfrom being stressed in the initial position of said jaws, a ball holder and an anvil positioned-on spring.

m the pposing Jaws, mspectively,'means to subject .s'rro LENNART EzSON m 

